A gas is collected at 740. mmHg and 23.0 degrees C. The subsequent volume is not measured until the next day when the pressure is 745 mmHg and the temperature is 20.0 degrees C, at which time the volume is found to be 15.3 mL. What was the original volume

Which process does not require the presence of a physical substance in order to transfer heat? air in the atmosphere is heated by the ground. this warm air then rises, and cooler air falls. this is an example of what type of process? how is conduction different from radiation?

What is the ph of a solution that has a hydrogen ion concentration of 1.0 * 10 -9 m?

Why is the melting of ice a physical change ?